POS1477 DISEASE FLARES AFTER SARS-COV-2 MRNA VACCINATION IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS ARE ASSOCIATED WITH DISEASE ACTIVITY BEFORE VACCINATION
Authors: J. Kikuchi, Y. Kondo, S. Kojima, S. Kasai, Y. Sakai, M. Takeshita, K. Hiramoto, S. Saito, H. Fukui, K. Suzuki, Y. Kaneko
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> While some reports suggest the development and flare of autoimmune inflammatory rheumatic diseases after vaccination, the frequency of disease flare after vaccination in patients with systemic lupus erythematosus (SLE) has been reported to be low. When we assess risk-benefit balance of vaccine administration, it is crucial to understand the effect of vaccines in patients with SLE. However, SARS-CoV-2 mRNA vaccines are new types of vaccines, and little is known about the effectiveness and safety of the vaccines and factors associated with disease flare in patients with SLE after SARS-CoV-2 mRNA vaccination. <h3>Objectives</h3> To elucidate the effect of SARS-CoV-2 mRNA vaccinations including adverse reactions to vaccines, neutralising antibody titres and disease flare rates after their vaccination and the associated factors in patients with SLE. <h3>Methods</h3> We enrolled the uninfected patients receiving two doses of vaccine (BNT162b2 or mRNA-1273) between June and October 2021. The neutralizing antibodies in peripheral blood, adverse reactions, and disease flares defined by the SELENA-SLEDAI Flare Index were evaluated four weeks after the second dose of vaccine. The neutralizing antibodies were measured using the STACIA SARS-CoV-2 Neutralization Antibody Test (MBL Corporation, Nagoya, Japan), and the cut-off level of seroconversion was defined as an antibody concentration of more than 1.67 U/mL. <h3>Results</h3> Ninety SLE patients were enrolled. The median age was 46.5 years, and the disease duration was 9.0 years. The median SLEDAI before vaccine administration was 2. Four weeks after the second dose of vaccination, 19 (21.1%) were still negative for neutralising antibodies. Adverse reactions were observed in 88.9%, including fever above 37.5° C in 20.8%. Factors associated with negative neutralising antibodies were older age, anemia (Hb ≤ 11 g/dL), mycophenolate mofetil (MMF) use (p=0.030 [55 years vs 44 years], p=0.014 [36.8 % vs 11.3%], and p=0.029 [42.1% vs 16.9%], respectively). Regarding disease activity, SLEDAI modestly but significantly increased significantly vaccination (p=0.016, median change 0 [IQR: 0–1]). Thirteen (14.4%) and 4 (4.4%) patients experienced flares and severe flares (nephritis in 3 and vasculitis in 1), respectively. High titres of SLEDAI, anti-dsDNA antibodies, rash, and azathioprine use were associated with flares in univariate analysis (p=0.046, p=0.034, p=0.037 and p=0.038, respectively, Table 1). Multivariable logistic regression analysis showed that high levels of SLEDAI and anti-dsDNA antibodies were associated with flares. Types of vaccines, neutralising antibody titres, and frequency of adverse reactions were not relevant for flares. <h3>Conclusion</h3> Older age, anemia, and MMF use are associated with negative seroconversion of neutralising antibodies. Residual disease activity before vaccination is a risk factor for flares. <h3>References</h3> [1]Connolly CM, et al. Arthritis Rheumatol. 2022; 74: 28-32. [2]Nune A, et al. QJM. 2021; 114: 739-740. [3]Yoshida T, et al. Lupus Sci Med. 2022; 9: e000727. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.